block: ll_rw_blk.c split, add blk-merge.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/Makefile b/block/Makefile
index 2002046..5a43c7d 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -4,7 +4,7 @@
 
 obj-$(CONFIG_BLOCK) := elevator.o blk-core.o blk-tag.o blk-sysfs.o \
 			blk-barrier.o blk-settings.o blk-ioc.o blk-map.o \
-			blk-exec.o ioctl.o genhd.o scsi_ioctl.o
+			blk-exec.o blk-merge.o ioctl.o genhd.o scsi_ioctl.o
 
 obj-$(CONFIG_BLK_DEV_BSG)	+= bsg.o
 obj-$(CONFIG_IOSCHED_NOOP)	+= noop-iosched.o